1. FIELD OF THE INVENTION
The present invention relates to feeder devices for feeding increments of a sheet stock material at preselected intervals.
2. PRIOR ART
The feeding of sheet material with reciprocating feeders has long been a problem, due in large part to the need for promptly feeding a precise increment of material into a punch press between strokes. At the present time, the most common feeders comprise intermittently operated feed rolls that drive the stock into the press. In addition, some types of direct gripping, linear, reciprocating feeders are utilized, but these generally have to be operated at relatively slow speeds, or the gripper that is used for gripping this sheet material will tend to tear out because of the inertia of the sheet. Further, the guiding of the sheets has been a problem because the sheet is usually pushed through guides. The sheet then tends to buckle or crease, or the conventional feeder will skew the sheet slightly during the feeding operation causing a jam in the press.